Dust collecting head



April 1958 R. E. BROCHETTI 2,829,867

nus'r COLLECTING HEAD Filed June 21, 1954 2 Sheets-Sheet 1 12-. 2 6 21 w 1? J0 ,"X 5 1 /-4 INVENTOR.

United States DUST CGLLECTEN G HEAD Raymond E. Brochetti, Churchill Borough, Pa., assignor to Mine Safety Appliances Company Application June 21, 1954, Serial No. 437,945

6 Claims. (Cl. 255--50) This invention relates to dust collecting heads, and more particularly, to those designed for collecting dust resulting from drilling operations, such as drilling of holes for mine roof bolts.

it is the current practice to support mine roofs by over head bolts instead of by props extending from the floor to the roof of the mine. The bolts are inserted into holes that have been drilled through the roofs. During the drilling of these holes and during other such drilling operations, a great deal of particulate matter is formed resulting in heavy clouds of dust with all of the well-known disadvantages.

it is among the objects of this invention to provide a suction dust collecting head by which substantially all dust and larger particulate matter can be carried away to a collector by an efiicient high velocity air current and thereby maintain the atmosphere around the drilling opand a tubular nozzle extending angularly of the housing.

An air and dust passage is formed by the housing and nozzle. A resilient disk is carried by the housing for placement against the roof of the mine, for example, and provides an air seal for the collecting head. The tubular nozzle contains an outlet for connection to a suction means, such as dust collector apparatus, and the housing, at its lower end, contains a sleeve through which a drill extends into engagement with the mine roof. The housing, including the sleeve, is designed to permit removal of the drill without displacement of the collecting head from the mine roof, and the sleeve closely surrounds the drill to permit admission of air between the sleeve and the drill to provide a high velocity air inlet.

Other objects and advantages will become apparent in the following description and annexed drawings in which:

Fig. 1 is a plan view of the collecting head;

Fig. 2 is a vertical longitudinal section through the.

collecting head in its operative position relative to a drill;

Fig. 3 is a vertical transverse section taken on line Ill-III of Fig. l;

Fig. 4 is afragmentary modified form. of the collecting head taken on line IV--IV of Fig. 5;

Fig. 5 is a vertical longitudinal section through the collecting head shown in Fig. 4; and

Fig. 6 is a vertical transverse section taken online VI-VTof Fig. 4. 1

Reference is now made to the drawings wherein the atent C 2,829,867 if Patented Apr. 8, 1958 2' dust collecting head 2 is shown as comprising a cylindrical housing 4 and tubular nozzle 6. Collector head 2 is supported in a conventional manner by a jack, or the like, through support 7 which normally extends from a drilling machine and may be adjusted upwardly or downwardly. The drilling machine also carries adrill 8 for movement into and'ont of housing 4. The head 2 and drill 8 are positioned relative to each other on the drilling machine whereby the drill may be inserted or removed centrally of the housing 4. i The'nozzle 6 is arranged for connection to a su'ctionhose 10 which, "in turn, is connected to a dust collector device of a type well known in the art. Housing 4 is constructed of a'relatively' hard material, such as metal, and forms a dust inlet portion 11 at. its upper end and an air inlet portion 12 at its lower end. A removable sleeve 13 is removably connected to air inlet 12 by'bolts 1,4,o1' the like, and extends-upwardly for coextensive or coplanar relationship with shoulder 15. The size of the sleeve is predetermined to closely surround the drill and', at the same time, readily permit removal of the drill without disturbing the position of the collecting head}. When the drill 8 is inserted through housing 4, an annular space 16 is formed between the Y drill and the sleeve 13 to provide a high velocity air inlet for the head. As dilferent size drills are use, the size of the sleeve is varied in order that the maximum velocity air inlet may be maintained with a given drill size. It should be clear that, as the annular space 16 is decreased in radial cross-sectional area, the air inlet velocity is increased. r

A flat, flexible disk 18, in its normal configuration, containsa centrally disposed opening of a diameter slightly smaller than the outside diameter of the upper end of the housing 4. Disk 18 is stretched over the upper end of the housing, and as the disk is mounted on the housing, it will deform to assumethe shape of an inverted tnmcated cone as is readily seen in Fig. 2. The flexibility and the resiliency of the disk 18 in its conelike shape.

permitsthe collectinghead 2 to be placed against the may be'placedaround the bottom of disk 18 for securing the disk to the housing 4, but it' has been found that the ring is not necessary in most operations since the stretching of the disk over the housing is sufiicient to provide a good securing means and prevents air leakage. The noz zle 6 of the collecting head is integrally connected to the housing. 4 and is disposed at an angle thereto so that clearance is always available between the sleeve 6 and suction hose 10 and the surface to be drilled; thus, the head may be easily placed against irregular surfaces without hindrance. Nozzle 6 and housing 4 provide a high velocity suction passage 20 for the particulate matter emanating from the drilled hole. Passage 20 is constricted at-the area above shoulder 15 and sleeve 13 (Fig. 2) to form a constricted throat 21 and terminating into cuts 24 formed halfway around the inner Wall 22 of the housing above sleeve 13 to form a pair of similar passage terminal portions 241:. Throat 21, Fig. 2, is coincidental with a vertical arcuate' plane intersecting the junction of nozzle 6 and housing 4 at shoulder 15. Terminal portions 24a of passage 20 extend from throat 21 to diametrically opposed: points on inner wall 22 and provide a means for extending-thethroat suction velocity for greater pick=up of dust at areas which normally would contain a diminished v'clocitydue to their distance from thoat 21. Looking at the right hand side of Fig. 2, it is readily seen that, in order to collect the dust sifting downwardly between drill 8 and housing 4, the air passing by sleeve 13 must be maintained at -a velocity sutficient to carry the dust to throat 21. Since terminal portions 24a extend the high velocity available at throat 21 to provide this necessary velocity, efliciencyof the collecting head 2 is assured in that dust will not'clog the housing 4. Also, positioning the top of sleeve 13 in coextensive or coplanar relationship with shoulder 15 prevents any sudden velocity drop of the air admitted past the sleeve and entering the throat 21. Thus, the air is conveyed from the points of admission through the sleeve in a continuously smooth manner without appreciable turbulence due to deleterious velocity changes. Furthermore, the complete passage as formed by sleeve 13 and housing 4 provides a means of evenly and gradually diminishing the air velocity from the points of air admission to throat 21 and in this manner insure maintenance of higher velocities in the housing 4. The utilization of this eflicient construction permits easy selection of a correctly rated suction means of the dust collecting device.

Referring to Fig. 2, attention is directed to the fact that the annular space between the drill 8 and wall 22, taken radially, is smaller than the vertical cross-sectional area of throat 21 for'the highly advantageous purpose of permitting only drilled particles smaller than throat 21 to gravitate past the drill. It is thus obvious that passage cannot become'clogged to thereby break down the operation of the collector unit. Asth'e hole is drilled, the particles falling into chamber 4 are crushed to the predetermined size between the drill 8 and wall 22 by the action of the metal drill against the metal housing. Crushing vanes, or the like, may be incorporated'in the wall 22, but no advantage over the illustrated smooth construction has been apparent.

In operation, the collecting head 2 ismoved upwardly against the surface in which a hole is to be drilled with the resilient disk 18 placed tightly against the surface. The drill 8 is positioned through the collecting head to extend centrally of the housing 4. Prior to the movement of the drill through the housing, a sleeve 13 of proper size is mounted in'the housing and closely surrounds the drill in its operative position. The dust collector device, which is attached to nozzle 6 of the collecting head by a suction hose 10, is started to induce air between the sleeve and drill while the drill is boring the hole. As the particulate matter gravitates from the drilled hole, it sifts downwardly between the housing and drill and is induced toward the dust collector device by the high velocity air stream. The larger particulate matter is ground or crushed between the drill and housing to prevent clogging of the collecting head. The construction of the dust and air passage through thehousing and nozzle permits removal of all of the dust resulting from the drilling operation. =When the drill'requires replacement, it is necessary only to remove the drill from the housing without disturbing the collecting head or shutting down the dust collector device.

Referring to Figs. 4, 5 and 6, it is seen that this modified form of the invention is quite similar to the preferred form shown in Figs. 1, 2 and 3 andrequiresonly a brief explanation to point out the distinguishing'features. The dust collecting head 26 comprises a tubular housing 28 and a tubular nozzle 30 made of either metal or plastic material. The housing 28 includes a full. length sleeve 32 of metal or other such hard material and having an aperture 34 conforming in shape to a constricted throat 36 of passage 38; Throat 36 is coincidental with a vertical arcuate plane intersecting the junction of housing 28 and sleeve 32 at passage 38. The aperture 34 cooperates with throat 36 to form passage terminal portions 40 sim ilar to the one shown at 24a in the preferred embodiment. Sleeve 32 provides an efficientgrinding surface for the particulate matter emanating from the drilled hole and closely surrounds the drill-toprovide ajhigh velocity air inlet. Sleeve 32 also comprises at" 1 383 12 which is inaszasev 4 serted into recess 43 of the housing 28 for removably l0- cating the sleeve within the housing. The head includes a flexible disk 44 identical to disk 18 and mounted on the housing as fully described above. By modifying the collecting head in this manner to include a full length sleeve, it is possible to produce a smoother path for the dust and air and thus enhance the'dust pick-up qualities of the head. Furthermore, according to the modified construction, a large selection of materials for fabrication of the major portion of the head is available since any crushing of particulate matter is performed between the sleeve and drill.

Having explained the principle of the present invention and having illustrated and described what is considered to be the best embodiment, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. A collecting head adapted for placement against a surface for receiving dust particles drilled from the surface by a drill comprising a tubular housing having a dust inlet and an axially opposed air inlet, said air inlet including a removable sleeve adapted to be slightly spaced from the drill, a tubular nozzle extending from said housing intermediate said inlets, said housing and nozzle forming an air and dust passage, said passage being constricted at the junction of the housing and nozzle and diverging outwardly away from said housing, and the upper surface of said sleeve being coextensive with and at least partially forming the lower surface of said constriction.

2. A collecting head adapted for placement against a surface for receiving dust particles drilled from the surface by a drill comprising a tubular housing having a dust inlet and an axially opposed air inlet, a tubular nozzle extending from said housing intermediate said inlets, said housing and nozzle forming an air and dust passage, said passage being constricted at the junction of the housing and nozzle and diverging outwardly away from said housing, said air inlet including a removable sleeve positioned coextensively with and at least partially forming the lower surface of said constriction, and the interior of said housing extending said constriction away from said nozzle at least partially around said housing above said sleeve.

3. A collecting head for receiving dust particles drilled from a surface by a drill comprising a tubular housing having a dust inlet including a sealing disk adapted for placement against the surface, said housing having an air inlet axially opposed to said dust inlet, said air inlet including means adapted to be slightly spaced from the drill and having an upper end, a tubular nozzle extending from said housing intermediate said inlets, said housing and nozzle forming an air and dust passage, said passage being constricted at the junction of the housing and nozzle and diverging outwardly away from said housing, the upper end of said means being coextensive with the lower surface of said constriction, and said passage extending from said constriction away from said nozzle into and at least in part around said housing.

4. A collecting head adapted for placement against a surface for receiving dust particles drilled from the surface by a drill comprising a tubular housing having a dust inlet and an axially opposed air inlet, a tubular nozzle extending from said housing intermediate said inlets, said housing including a removable sleeve, said sleeve, housing and nozzle forming an air and dust passage, said passage being constricted adjacent the junction of the housing and nozzle and diverging outwardly away from said housing; said sleeve having an opening conforming to the 'shape of said constriction and extending said constriction away from said nozzle at least partially around said housing.

5. The combination with a drill for drilling a hole in a surface, of a collecting head adapted for placement against the surface comprising a tubular housing having a dust inlet and an axially opposed air inlet, said housing including a removable sleeve positioned at least in said air inlet and said drill extending through said housing within said sleeve, a tubular nozzle extending from said housing intermediate said inlets, said housing, sleeve, drill and nozzle forming an air and dust passage, said passage being constricted adjacent the junction of the housing and nozzle and diverging outwardly away from said housing, and said housing and sleeve extending said constriction away from said nozzle at least partially around said drill.

6. A collecting head adapted for placement against a surface for receiving dust particles drilled from the surface by a drill comprising a tubular housing having a dust inlet and an axially opposed air inlet, said housing including a removable sleeve positioned at least in said References Cited in the file of this patent UNITED STATES PATENTS 2,107,552 Smith Feb. 8, 1938 2,107,864 Hunter Feb. 8, 1938 2,279,186 Terry et al. Apr. 7, 1942 FOREIGN PATENTS 266,630 Great Britain Mar. 3, 1927 

